One of the big selling points of the Speedo Fastskin FSII was that it was developed using biomimetics, cribbing good design from nature. So how well does it compare to the actual sharks on which it was modelled? It turns out... not so great.

While the suits may have a lot else going for them that help swimmers perform better, their attempts to mimic the natural abilities of sharkskin have failed, at least according to research published in the Journal of Experimental Biology. Researchers at Harvard university took strips of sharkskin, and using a flow tank they analyzed how it hydrodynamic it was in moving water.

They compared this to more sharkskin, but with the denticles sanded down, and against Speedo's cutting edge technology. In fact, it all comes down to those denticles, which are tiny little tooth-like structures that serve as the scales of the animals. On sharks, they create vortexes in the water as the creature swims, which serve not only to reduce drag, but as the researchers found out, also create thrust. Image via Getty Images.

That's right, sharkskin actually gives the sharks a physical boost.

"What we found is that as the shark skin membrane moves, there is a separation of flow – the denticles create a low-pressure zone, called a leading-edge vortex, as the water moves over the skin," said researcher Professor George Lauder. "You can imagine this low-pressure area as sucking you forward. The denticles enhance this leading-edge vortex, so my hypothesis is that these structures that make up shark skin reduce drag, but I also believe them to be thrust enhancing."

And the Speedo did none of that. It looks like Speedo's going to have to do a bit more work before successfully copying evolution.